Could be: Chalcocite, Galena, Molybdenite, Stibnite, or Jamesonite.
The mineral Quartz leaves a colorless streak.
Magnetite can be black and it has a black streak. It is metallic and iron ore
Hematite can appear gray in color, but will exhibit a reddish to rust-colored streak.
The streak of a mineral is much more accurate in identifying a mineral than color. The streak of a mineral can distinguish minerals with metallic and non-metallic luster. For example, metallic minerals generally have a dark streak whereas non-metallic luster minerals often have a light colored streak.
diamond
to find the minerals streak, what i the mineral rubbed in
Even though it's a blackish/brown mineral, it leaves a WHITE streak.
Streak Test, because nonmetallic minerals typically streak colorless/white, and metallic minerals typically streaks dark/characteristic color.
Magnetite
The mark is called a streak and the color depends on what mineral you are testing.
the color a mineral leaves on a white tile
It is called the streak test. It can help identify the mineral by the color of the streak that is left.